1. Field of Invention
The present invention relates to lock and key, and more particularly to a lock assembly comprising a barometric lock cylinder associated with a barometric key to provide not only the locking permutations but also the barometric engagement so as to ensure the security function of the locking assembly.
2. Description of Related Arts
The conventional lock and key assembly, such as barrel lock, utilizes specific engagement or disengagement between a plurality of pin-tumblers in the lock cylinder and the key""s serrations correspondingly to control the locking and unlocking functions thereof.
Virtually, all mechanical locking devices are subject to tempering, possibly resulting from loss of keys, duplication of keys, and picking due to its limited mechanical structure and theory. Thus, the pin-tumblers of such conventional lock assembly can be seen through the lock cylinder such that the pin-tumblers can respectively be pressed in order to unlock the lock assembly.
Moreover, the serrations of the key may be repeatedly duplicated such that the key can open several locks by fully inserting the key into the lock cylinder or just half way of the lock cylinder to match the pin-tumblers thereof.
For security purpose, an electronic lock assembly having a predetermined cipher preset therein is provided recently. However, the electronic lock assembly is too expensive to install since it must be incorporated with a computer such that the electronic lock assembly cannot be popular in use. Thus, the electronic lock assembly can be easily opened by someone who hacks in the computer or by decoding the cipher.
A main object of the present invention is to provide a lock assembly which comprises a barometric lock cylinder associated with a barometric key to provide not only the locking permutations but also the barometric engagement so as to ensure the security function of the locking assembly.
Another object of the present invention is to provide a lock assembly which avoids the drawbacks of easy picking and key duplicating of the conventional mechanical lock and key assembly by eliminating the serrations of the keys with a simply rod liked magnetic key to associate with a mechanical lock cylinder by fitting into a circular keyway thereof.
Another object of the present invention is to provide a lock assembly wherein the arrangement of the tumblers, which is not limited to one or two opposing rows as in the mechanical lock and key assembly, can include any possible number of tumblers aligned around anywhere of the entire cylindrical surfaces of the key and keyway correspondingly, so that the present invention can provide more locking permutations and combinations to ensure the security function of the lock assembly.
Another object of the present invention is to provide a lock assembly which requires a barometric engagement between the lock cylinder and the key such that even though the key""s serrations match the tumblers of the lock cylinder, the lock assembly cannot be opened without matching the barometric engagement.
Another object of the present invention is to provide a lock assembly which further comprises a cipher lock arrangement preset in the lock cylinder so as to further ensure the security function of the lock assembly.
Another object of the present invention is to provide a lock assembly wherein the tumblers are hidden behind the lock cylinder surfaces, which cannot be seen through the keyway, so as to prevent the lock assembly from being intentionally unlocked by any tools through the keyway.
Accordingly, in order to accomplish the above objects, the present invention provides a lock assembly, comprising:
a barometric lock cylinder for actuating a latch assembly wherein the barometric lock cylinder comprises:
a lock sleeve having an axial rotor hole and a plurality of tumbler sockets radially distributed on an inner surface of the lock sleeve;
a plurality of tumblers being coaxially placed in the tumbler sockets respectively;
a tubular lock core being rotatably and coaxially fitted in the axial rotor hole of the lock sleeve to define a keyway therethrough, the lock core having a plurality of locking holes radially distributed on an outer circumferential surface of the lock core and a plurality of air channels radially distributed on an inner circumferential surface of the lock core for communicating with the locking holes respectively, wherein each of the locking holes is capable of coaxially aligning with the tumbler sockets respectively; and
a plurality of resilient elements being coaxially disposed in the tumbler sockets respectively for applying urging pressures on the tumblers to move inwardly towards the locking holes until an inner portion of each of the tumblers is disposed in the respective locking hole and an outer portion of the tumbler is disposed in the respective tumbler socket so as to lock up the rotatable movement between the lock core and the lock sleeve; and
a barometric key comprising:
a key head having a compressible air chamber provided therein; and
a key body having an air conduit longitudinally extended from the air chamber and a plurality of airways, which are radially extended through the air conduit respectively, provided around the key body corresponding to the axial and radial positions of the air channels in the barometric lock cylinder respectively, such that when the barometric key is inserted into the keyway, a predetermined air pressure applied from the key head is adapted to drive the tumblers to move outwardly into the tumbler sockets correspondingly, so as to unlock the barometric lock cylinder to enable the lock core freely rotating to control the locking and unlocking of the latch assembly.